The problem with cell phone searches is that some states have no-phone-while-driving laws, but in order to verify you were on the phone with facts you need to search it. Otherwise, it'd be an unjustified arrest. Without searching the phone, the law is unenforceable.
The question then becomes what information can they use to prosecute you? I believe they should be allowed to search your phone, but only are able to use time stamps of texts and phone calls. If they search your phone without a warrant they shouldn't be able to use stuff they find (like say, underage nude pics on a teen chicks phone) against you, since that's not the proper way to conduct an investigation. That evidence should not be admissible to the court, I'm sure a good lawyer could argue that.
However, after you've been arrested, aren't police already permitted to search say, your vehicle? If yes, then why not your phone? Probable cause and all is effectively a warrant.
The question then becomes what information can they use to prosecute you? I believe they should be allowed to search your phone, but only are able to use time stamps of texts and phone calls. If they search your phone without a warrant they shouldn't be able to use stuff they find (like say, underage nude pics on a teen chicks phone) against you, since that's not the proper way to conduct an investigation. That evidence should not be admissible to the court, I'm sure a good lawyer could argue that.
However, after you've been arrested, aren't police already permitted to search say, your vehicle? If yes, then why not your phone? Probable cause and all is effectively a warrant.